Leukocyte/endothelium activation and interactions during femoral percutaneous transluminal angioplasty

Colchicine Inhibits Intimal Hyperplasia and Leukocyte VEGF Expression in Dogs

BACKGROUND

Restenosis due to intimal hyperplasia following percutaneous transluminal angioplasty limits its long-term efficacy. We evaluated the effect of colchicine on the development of intimal hyperplasia following balloon angioplasty and on the vascular endothelial growth factor (VEGF) expression in leukocytes.

MATERIAL AND METHODS

Adult dogs underwent balloon angioplasty of the right iliofemoral artery. Group 1 served as control, while groups 2 and 3 (six animals per group) received 0.1 and 0.5 mg/kg/d of colchicine p.o., respectively, starting 2 d before angioplasty and continued for 14 d. Before angioplasty and at day 14, blood samples were collected for drug toxicity analysis and the determination of leukocyte expression of VEGF. Animals were euthanized and iliofemoral arteries were perfusion fixed in situ and processed for histological and morphometric analysis.

RESULTS

Balloon angioplasty without colchicine resulted in 446% (P < 0.001), 111% (P = 0.7), and 267% (P < 0.001) increase in intimal and medial thickness and intima/media ratio compared with contralateral uninjured iliofemoral arteries. Low-dose and high-dose colchicine resulted in 32% and 58% reduction in intima/media ratio, respectively (both P < 0.001). VEGF expression in leukocytes of control group was up-regulated (40%), but was down-regulated by 12% and 55%, respectively, in low-dose and high-dose colchicine groups at 2 wk after angioplasty compared with preangioplasty expression. The results of complete blood count and serum transaminases and creatinine were within normal range.

CONCLUSION

This study demonstrates that oral colchicine for 2 wk significantly reduces intimal hyperplasia following balloon angioplasty in dogs through down-regulation of leukocyte VEGF expression and without apparent toxicity.

Renal angioplasty causes a rapid transient increase in inflammatory biomarkers, but reduced levels of interleukin-6 and endothelin-1 1 month after intervention

OBJECTIVE

To examine prospectively whether inflammatory biomarkers and endothelin (ET)-1 are increased in patients with renal artery stenosis (RAS), and to investigate how treatment with percutaneous transluminal renal angioplasty (PTRA) affects these variables during the first month after intervention.

METHODS

One hundred patients with suspected RAS undergoing renal angiography were included. PTRA was performed if the trans-stenotic mean arterial pressure gradient was>or=10 mmHg. High-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNFalpha), neopterin, CD40 ligand (CD40L) and endothelin-1 (ET-1) were measured before, and 1 day and 1 month after PTRA (n=61) or diagnostic angiography only (n=39).

RESULTS

At baseline there were no significant differences in inflammatory biomarkers or ET-1 levels between patients subsequently undergoing PTRA or angiography only. After angiography, IL-6 and hs-CRP had increased in both groups compared to baseline (P<0.001). At this time point hs-CRP (10.90+/-1.48 versus 6.37+/-1.61 mg/l; P<0.05) and IL-6 (13.70+/-0.94 versus 13.00+/-0.17 pg/ml; P<0.01) were higher in the PTRA group than in patients subjected to angiography only. One month after PTRA, systolic blood pressure and levels of IL-6 and ET-1 were lower than before intervention (P<0.05), whereas CD40L had increased compared to baseline (P<0.01).

CONCLUSION

In patients with RAS, PTRA triggers rapid transient increases in hs-CRP and IL-6; however, 1 month after PTRA, both IL-6 and ET-1 had decreased compared to before intervention, indicating beneficial effects of PTRA on inflammation and the endothelin system.

Standardized immune monitoring for the prediction of infections after cardiopulmonary bypass surgery in risk patients

BACKGROUND

Infections are the most common cause of late complications in cardiopulmonary bypass (CPB) surgery patients, and are difficult to predict. Here we studied the diagnostic value of a standardized immune monitoring program based on recent advances in flow cytometry (exact quantification of surface-marker expression) and cytokine determination (semiautomatic systems).

METHODS

CPB patients (56) at risk for complications (age >70 years and/or preoperative left-ventricular ejection fraction < 25 %) were classified into three groups: without (33), with suspected (14), and with confirmed (9) infection. Applying the Quantibrite trade mark -system, we daily quantified the expression of CD11b, CD64, CD71, CD86, and HLA-DR on monocytes/granulocytes. Furthermore, the ex vivo secretion of tumor necrosis factor (TNF)-alpha as well as the plasma interleukin (IL)-10 levels were determined by a semiautomatic system. Ex vivo elastase release was measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

All patients showed signs of granulocyte activation and monocyte deactivation. Monocytic HLA-DR and plasma IL-10 were the best markers to discriminate patients with infection from those without as early as day 1. Using a cutoff of 5792 HLA-DR molecules per cell, both sensitivity and negative predictive value for patients who developed microbiologically confirmed infection was 1.0, and the area under the curve (AUC) was 0.85.

CONCLUSIONS

Our data suggest that a standardized immune monitoring at day 1 might be useful for early discrimination of patients at elevated risk for infections.